Create a Compound Clip from an Image

1) Locate the clip on your timeline making sure it has no effects currently applied to it

2) Right-click on the clip and choose "New Compound Clip…"
3) Apply the effect to the Compound Clip instead
The above technique works with any element on the timeline, but it brings the most benefits when used with high-resolution photos. When a Compound Clip is created, the resolution will match that of the timeline where the clip is used. This speeds up rendering considerably, as any effects you apply to the Compound Clip need only to be processed at the resolution of your frame, rather than the original resolution of the photo (which may be many times larger).